/*
 * Copyright:  2018 smarabbit studio.
 *
 *  Licensed under the Confluent Community License; you may not use this file
 *  except in compliance with the License.  You may obtain a copy of the License at
 *
 *  http://www.confluent.io/confluent-community-license
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 *  WARRANTIES OF ANY KIND, either express or implied.  See the License for the
 *  specific language governing permissions and limitations under the License.
 *
 *  @作   者： 黄开晖 (117227773@qq.com)
 *  @日   期:  2020年9月13日
 */
package com.massyframework.beanskin.service;

import java.util.Comparator;

import com.massyframework.beanskin.util.version.Version;

/**
 * 服务版本比较器
 * 
 * <p>
 * 版本高的排序在前，版本低的排序在后。
 * @author huangkh
 *
 */
public class ServiceVersionComparator implements Comparator<ServiceReference<?>> {

	/**
	 * 
	 */
	public ServiceVersionComparator() {
		
	}

	@Override
	public int compare(ServiceReference<?> o1, ServiceReference<?> o2) {
		Version v1 = o1.getServiceVersion();
		if (v1 == null) {
			v1 = Version.emptyVersion;
		}
		Version v2 = o2.getServiceVersion();
		if (v2 == null) {
			v2 = Version.emptyVersion;
		}
		
		return v2.compareTo(v1);
	}

}
